Port polishing, roughing used at the time of stepped modification. I installed and used in electric Ryuta of the flexible shaft.
It will be shortening of interesting as scraping and working time without bouncing. The rough work is required item.

Is helpful because it can be used to poke at the tip because the bullet type that with a blade to the tip.
In addition, since that can be cut to clean, it will come in handy in cutting operations that require delicacy.
Since the carbide metal also shaved skinny.